This invention relates generally to magnetoresistive sensors and, more particularly, to making very narrow trackwidth current-perpendicular-to-plane (CPP) devices.
Magnetic disk devices are used to store and retrieve data for digital electronic apparatus such as computers. Due to its excellent characteristics, the hard disk drive has found increasingly wide applications, including a motion picture recorder/player, a car navigation system reader/recorder, and a removable memory for use in a digital camera. Providing narrow track widths in a magnetic recording head or sensor is important to improving the performance of a hard disk drive by increasing the areal density, i.e., the number of data bits that can be stored and retrieved in a given area. As track widths of magnetic recording heads become increasingly narrow, the tooling required to define such narrow track widths becomes increasingly expensive. This is especially true as the critical dimensions of magnetic recording heads become comparable to or smaller than those in the semiconductor industry. In the case of very small dimension CPP devices, it becomes increasingly difficult to make a good contact to the top electrode of the CPP device.